A robot that uses sensor inputs for attention activation and corresponding methods, systems, and computer programs encoded on computer storage media. The robot can be configured to compute a plurality of attention signals from sensor inputs and provide the plurality of attention signals as input to the attention level classifier to generate an attention level. If a user is paying attention to the robot based on the generated attention level, the robot selects a behavior to execute based on the current attention level, wherein a behavior comprises one or more coordinated actions to be performed by the robot.